Issue

Instructions on how to set the time on an ION73xx meter using Modbus.

Product Line

ION7300 Series (ION7300, ION7330, ION7350)

Environment

ION73xx meters – Time configuration using Modbus protocol

Resolution

Using the Modbus protocol, it is possible to set the time on ION7300 series meters. This process is not a time synchronization (since there is no external source continuously sending a signal), but you can use Modbus software to automate the process by retrieving time from a source and passing it to the meter.

To set the Meter time via Modbus communications do the following:

1. Set the ION Clock Module Time Sync Source Register to the Modbus
communications port.

2. Write the UNIX time in seconds as an unsigned 32-bit value to Modbus
Registers 41926 (high order) and 41927 (low order).

Steps to Set Time via Modbus

1. Convert the desired time to UNIX time (seconds since 01/01/1970 UTC).
2. Split the UNIX time into two 16-bit values:
• Lower order 16 bits → Register 41927
• Higher order 16 bits → Register 41926

Example

• UTC Time: 07/01/2009 02:00:01 AM
• UNIX Time: 1246413600 (decimal)
• Binary: 0100 1010 0100 1010 1100 0011 0010 0000
• Lower order bits: 1100 0011 0010 0000 → 49952 (decimal)
• Higher order bits: 0100 1010 0100 1010 → 19018 (decimal)

Write:

• 49952 to register 41927
• 19018 to register 41926

The meter will now display the correct time and continue ticking based on its internal clock.